There are new standards and regulations being created and enforced by the FCC for 911 calling when using Voice over IP (VoIP) applications. The National Emergency Number Association (NENA) published its interim i2 standards for mobile VoIP calls to connect callers in the IP domain with Public Safety Answering Points (PSAPs) supported by the existing E-911 service provider networks. NENA i2 compliance requires location information to be available for customers including the street address, floor and even cubicle number. NENA i3 addresses further specifications for an end-to-end emergency calling network.
When using a VoIP client on a mobile device, the default action when E-911 is dialed is to drop the client and place the call over the mobility network. Mobility typically uses cellular triangulation on the device to get the exact location of the user; however if a customer has no or poor mobile signal but can still connect via Wi-Fi they cannot place the 911 via the VoIP application. In certain circumstances VoIP applications are implementing an option in their client to identify when there is no signal and will then place the call over the VoIP application; however this is an all or nothing approach. If the customer has minimal signal or is flapping to a point that the E-911 call cannot complete it will not automatically fail-over to the VoIP application.